The objective in establishing the Chimpanzee Breeding and Research Program (CBRP) breeding colonies was to insure a steady supply of healthy chimpazees for future biomedical research needs. Genetic management of these chimpanzee colonies is a prerequisite for this goal. Sound genetic management requires genetic markers, which are essential for accurate pedigrees as well as for many research protocols. Thus, genetic management must begin with a search for informative new DNA markers, utilize them in paternity testing and the generation of high-quality corroborated pedigree data, yet still take probable future research needs into account. Since genetic management cannot effectively proceed without an explicit research effort, genetic management activities will be integrated with quantitative genetic analyses designed to exploit pre- existing research resources. Toward these ends, human short tandem repeat (STR) DNA markers which can be typed using PCR will be identified which reveal informative polymorphisms in chimpanzees. These markers will be used for paternity testing and pedigree corroboration, and for large- scale DNA typing of wild-born CBRP chimpanzees. These data will be used to characterize the amount of genetic variability present in African-born founders of the CBRP breeding populations, evaluate the degree of genetic divergence among the five CBRP colonies, formulate colony-specific breeding advice and identity replacement breeders. Pedigree data corroborated with DNA markers will also be analyzed with the tools of quantitative genetics to study the genetic basis of viral disease. Collaborative research will focus on the genetic epidemiology of Hepatitis C, the most frequent cause of transfusion-associated hepatitis in the United States. Over 240 chimpanzees have already been infected with HCV as part of earlier immunovirological research related to vaccine development. We will utilize these pre-existing data in a collaboration involving DNA typing, quantitative genetics, and immunophenotyping to investigate the genetic epidemiology of this infectious disease and thereby fully exploit the research value of these essential animal models.